State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China.
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China.
J Colloid Interface Sci. 2022 Nov;625:596-605. doi: 10.1016/j.jcis.2022.06.080. Epub 2022 Jun 22.
In this study, biochar derived from municipal sludge (SBC) was modified by CoFe-Layered double hydroxides (CoFe-LDH), and used as adsorbent and oxidant for the removal of ciprofloxacin (CIP) for the first time. Under the optimal conditions, the CIP removal rate is increased by 24% compared with the single SBC, while the removal rates of total organic carbon and total nitrogen in the modified one are increased by 24% and 27%, respectively. Mechanism investigation suggested that the specific surface area and adsorption sites of modified biochar increased, and more CIP was adsorbed to the composite surface and then oxidized by more environmental persistent free radicals contained in the CoFe-LDH@SBC, when the adsorbed CIP molecules was oxidized and degraded, the adsorption sites can be freed and thus new CIP could be adsorbed to the CoFe-LDH@SBC. In addition, the plausible degradation pathways of CIP were proposed according to high-performance liquid chromatography-mass spectrometry and density functional theory calculation. It not only reveals that CoFe-LDH@SBC has the high ability of adsorption and oxidation for CIP removal but also sheds novel insight into the application of biochar.
在这项研究中，首次将来源于城市污泥的生物炭（SBC）用 CoFe-层状双氢氧化物（CoFe-LDH）进行改性，用作吸附剂和氧化剂来去除环丙沙星（CIP）。在最佳条件下，与单独的 SBC 相比，CIP 的去除率提高了 24%，而改性生物炭的总有机碳和总氮去除率分别提高了 24%和 27%。机理研究表明，改性生物炭的比表面积和吸附位增加，更多的 CIP 被吸附到复合材料表面，然后被 CoFe-LDH@SBC 中包含的更多环境持久性自由基氧化。当被吸附的 CIP 分子被氧化和降解时，吸附位可以被释放，从而可以将新的 CIP 吸附到 CoFe-LDH@SBC 上。此外，根据高效液相色谱-质谱和密度泛函理论计算，提出了 CIP 的可能降解途径。这不仅揭示了 CoFe-LDH@SBC 对 CIP 去除具有高吸附和氧化能力，还为生物炭的应用提供了新的见解。
